The vitamin D is an important vitamin, which not only functions as a hormone, but also powers several systems throughout your body along with acting as a receptor for every single cell in your body.

When your skin gets exposed to sunlight, then vitamin D is made from cholesterol and apart from that, foods – fatty fish and dairy products (fortified) also promote vitamin D.

Even though the 400-800 IU is the daily recommended intake, but still the experts prescribes that you should take more than that, and taking less than the required amount will lead to the deficiency of vitamin D and which is by no means an uncommon occurrence. Studies have found out that there are about one billion people worldwide who have vitamin D deficiency with 82.1 percent are in the African-Americans alone followed by 69.2 percent of Hispanics and 41.6 percent in the US.

There are various risk factors which are associated with vitamin D deficiency such as –

*Being elderly, obese and overweight.

*Always staying indoors and using sunscreen when going out

*Eating fish in less amount

*Having dark skin

*Living far away from the equator where there is very little sun around the year.

*People who live near the equator gets frequent sun and hence, they are very less likely to have vitamin D deficiency as their body produces enough vitamin D to satisfy their needs of their body.

*The symptoms of the deficiency of vitamin D are normally very subtle and which is why most people doesn’t even notice them if it is having a negative impact on their life.



Vitamin D keeps the immune system of your body strong in order to fight the viruses that are known to cause illness by directly interacting with those cells that fight off infection.

Know this that if you are prone to getting sick too often, then the culprit is your vitamin D’s deficiency, furthermore proven by the study which shows a link between the deficiency and the respiratory tract infections. However, if Vitamin D supplements are taken at dosages of up to 4,000 IU daily, then the risk of the respiratory tract infections can be reduced.



Vitamin D deficiency can also lead to tiredness which is often overlooked as a potential cause. Not only that, low blood levels are also known to cause fatigue which negatively affects our body. But yes, vitamin D supplements can help to improve the symptoms of low blood levels – chronic daytime fatigue and headaches.



Vitamin D helps in maintaining the health of the bones through a number of mechanisms and one such mechanism is that it aids the body in the absorption of calcium.

Signs such as bone pain and pain in the lower back may be due to the inadequate levels of vitamin D in the body.

Various studies have found that there is a link between deficiency and chronic lower back pain as those with deficiency were more likely to have pain in the back which no doubt limits their daily activities.

One study has also shown that people with vitamin D deficiency were more likely to experience bone pain in their joints, legs and ribs as compared to those who have normal blood levels.



Depression may also be a sign of deficiency of vitamin D as one study has linked the deficiency of vitamin D to depression in adults (older).

Though many observational studies were carried out and in which a link had been found between low blood levels and depression, it is not accepted as it carries less weight than scientific studies; and also the latter one didn’t show any link between the two.

However, the researchers who had followed scientific studies had found that the dosages of vitamin D were very less as some of the studies may not have lasted long to see the effect of taking supplements.

Some scientific studies have shown that taking vitamin D supplements helps to improve the depression levels in deficient people.



If after surgery, the wounds heal slowly than the expected time, then it is a sure sign that the levels of Vitamin D are low.

Other studies had concluded that the production of compounds is increased by vitamin D and which is very important in the formation of new skin and a part of the wound healing process.

For proper healing, the role of vitamin D is very important as it controls inflammation and fights infections. If there is vitamin D deficiency, then healing can be jeopardised for those people as they would have high levels of inflammatory markers.

But the bad news is that there is very little to no research on this fact as to whether taking vitamin D supplements will have any positive effects on wound healing regarding the people with vitamin D deficiency.

However, one study has found out that patients (with leg ulcers) if treated with the vitamin in those people who have vitamin D deficiency, then their leg ulcers lessened by 28 percent.



Vitamin D plays a vital role in the absorption of calcium and bone metabolism.

However, it is seen that older woman believes that they need to take calcium if they are diagnosed with loss of bone but they are unaware that they may be needed to take vitamin D as there may be a deficiency.

The sign of the lower levels of the bone mineral density is a clear indication that calcium plus many other minerals are missing from bone, and it is this problem that places many older people at a risk of fractures, especially women.

A study was taken of more than 1000 middle-aged women (in menopause or post-menopause) were found to have a strong link between low vitamin D levels and low bone mineral density.

But a study had also shown that women (vitamin D deficient) were found to have seen no improvement in bone mineral density even if they took vitamin D supplements and their blood levels improved.

No matter what the findings are, it is a good plan to take adequate vitamin D and to maintain the normal blood levels so as to protect the bone mass and reduce the risks of fractures.



Stress causes loss of hair but when it becomes extreme then it is a sure sign that there is vitamin D deficiency.

Though low levels of vitamin D have been associated with female hair loss, yet there has been no conclusive study on that part.

An auto-immune disease and linked with rickets,  Alopecia areata’s signs are the severe loss of hair from the head and any other parts of the body and it is this very disease that causes soft bones in children who have vitamin D deficiency.

The disease Alopecia areata is also linked to the deficiency of vitamin D and people who have his disease along with lower blood levels tends to have severe hair loss.



The exact causes of muscle pain are often hard to pinpoint but there are evidences that points to vitamin D deficiency, furthermore proving by the fact that at least 71 percent of people (with chronic pain) were found to be lacking in vitamin D.

A study in rats had found out that deficiency in vitamin D led to sensitivity and pain due to the stimulation of nociceptors in the muscles; while a few other studies had found out that taking vitamin D supplements lowered the various types of pain considerably in those people who were suffering from vitamin D deficiency.



Vitamin D is very common and most of the times, many people doesn’t even notice it missing from their bodies. If you think that you are lacking in some vitamin, then without wasting any time, go see a doctor and get your blood levels checked and measured.

Luckily, vitamin D is very easy to treat – in short, you can either increase your exposure to the sun, eat more foods rich in vitamin D or you can take a vitamin D supplement and which in turn, will greatly benefit your body.


Stay tuned for part II tomorrow for more info on vitamin D importance.


When the discussions are made in regard to the topic of ‘health benefits from sun exposure’, usually it rounds on one term and that is ‘vitamin D’.


Marcelo is the co-founder and Director of Exercise Physiology at Intense Health, Perth's #1 Private Strength Training and Nutrition Clinics.


Marcelo is the co-founder and Director of Exercise Physiology at Intense Health, Perth's #1 Private Strength Training and Nutrition Clinics.